Hi angle shots
- Thread starter Alaskaman11
- Start date
Re: Hi angle shots
I am sure someone more knowledgeable/experienced will probably chime in, but I will give it a shot:
<span style="font-weight: bold">Corrections:</span>
Method 1: Considered more expedient, but not as precise.
Range to target X Slope Angle Factor = Assumed Range
i.e. Target is 100 yrds, SOF is .72, you now dial or hold as if the target is at 72 yards.
Method 2:
Take your correction at 0 Angle (Slope angle factor of '1')
multiply by your slope angle factor will give you your new correction.
Original correction X Slope angle factor = 'final' correction
i.e. Your elevation correction would be 6 MOA, the SAF to the target is .72, (6x.72=4.32) your new correction will be 4 1/4 MOA (Assuming your glass is graduated in 1/4 MOA, so obviously you just round)
<span style="font-weight: bold">For determining range only:</span>
When ranging your mil reading may be slightly incorrect, due to the appearance of the target being ranged. Keeping in mind that your constant is usually your largest margin of error for real world targets, it is usually advisable to use a horizontal constant for high angle shots. If this is simply not possible:
original range reading X SAF = corrected range
Again this is only necessary for vertical constants, as only they will be affected by appearance at angle. This is not precise at all, and hopefully someone will chime in with a better equation.
Hope this helps.
I am sure someone more knowledgeable/experienced will probably chime in, but I will give it a shot:
<span style="font-weight: bold">Corrections:</span>
Method 1: Considered more expedient, but not as precise.
Range to target X Slope Angle Factor = Assumed Range
i.e. Target is 100 yrds, SOF is .72, you now dial or hold as if the target is at 72 yards.
Method 2:
Take your correction at 0 Angle (Slope angle factor of '1')
multiply by your slope angle factor will give you your new correction.
Original correction X Slope angle factor = 'final' correction
i.e. Your elevation correction would be 6 MOA, the SAF to the target is .72, (6x.72=4.32) your new correction will be 4 1/4 MOA (Assuming your glass is graduated in 1/4 MOA, so obviously you just round)
<span style="font-weight: bold">For determining range only:</span>
When ranging your mil reading may be slightly incorrect, due to the appearance of the target being ranged. Keeping in mind that your constant is usually your largest margin of error for real world targets, it is usually advisable to use a horizontal constant for high angle shots. If this is simply not possible:
original range reading X SAF = corrected range
Again this is only necessary for vertical constants, as only they will be affected by appearance at angle. This is not precise at all, and hopefully someone will chime in with a better equation.
Hope this helps.
Re: Hi angle shots
These are the formulas I use to make my dope cards and it came directly from Sierra (and is the one they use in the Infinity software). Not exactly field friendly but if you are capable in excel you can pull info from a ballistics program and plug it into this formula to make your own table/card.
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/3.438) = Corrected MIL Sight Adjustment
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/1) = Corrected MOA Sight Adjustment
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/.955) = Corrected IPHY Sight Adjustment
The actual formula used for Mils set up for 1/10th mil "clicks"
=ROUND((((((E3-1)*'Data Sheet'!E36)+'Data Sheet'!F36)/((A15/100)*1.047)*'Data Sheet'!O3)/3.438)*10,0)/10*-1
Of course that formula is worthless unless you know what the "Data Sheet" looks like
Cheers,
Doc
These are the formulas I use to make my dope cards and it came directly from Sierra (and is the one they use in the Infinity software). Not exactly field friendly but if you are capable in excel you can pull info from a ballistics program and plug it into this formula to make your own table/card.
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/3.438) = Corrected MIL Sight Adjustment
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/1) = Corrected MOA Sight Adjustment
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/.955) = Corrected IPHY Sight Adjustment
The actual formula used for Mils set up for 1/10th mil "clicks"
=ROUND((((((E3-1)*'Data Sheet'!E36)+'Data Sheet'!F36)/((A15/100)*1.047)*'Data Sheet'!O3)/3.438)*10,0)/10*-1
Of course that formula is worthless unless you know what the "Data Sheet" looks like
Cheers,
Doc
Re: Hi angle shots
Thx guys, I tell ya, that makes me wish I paid better attention in math class in high school and college.
Thx guys, I tell ya, that makes me wish I paid better attention in math class in high school and college.
Re: Hi angle shots
Well roughly out to 500 yards with a 20* down or up angle your talking about 1/2 MOA (2.6") or less. So depending on your accuracy requirements hold a bit low and carry on. Now if your trying for a head shot at 900 yards with a 35* down angle you probably need to think about a calculator or moving closer
Cheers,
Doc
Well roughly out to 500 yards with a 20* down or up angle your talking about 1/2 MOA (2.6") or less. So depending on your accuracy requirements hold a bit low and carry on. Now if your trying for a head shot at 900 yards with a 35* down angle you probably need to think about a calculator or moving closer
Cheers,
Doc
Re: Hi angle shots
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: doc76251</div><div class="ubbcode-body">Well roughly out to 500 yards with a 20* down or up angle your talking about 1/2 MOA (2.6") or less. So depending on your accuracy requirements hold a bit low and carry on. Now if your trying for a head shot at 900 yards with a 35* down angle you probably need to think about a calculator or moving closer
Cheers,
Doc </div></div>
Thx Doc, I would like to do it on a cal, but I'm of the same mindset as you have.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: doc76251</div><div class="ubbcode-body">Well roughly out to 500 yards with a 20* down or up angle your talking about 1/2 MOA (2.6") or less. So depending on your accuracy requirements hold a bit low and carry on. Now if your trying for a head shot at 900 yards with a 35* down angle you probably need to think about a calculator or moving closer
Cheers,
Doc </div></div>
Thx Doc, I would like to do it on a cal, but I'm of the same mindset as you have.
These are the formulas I use to make my dope cards and it came directly from Sierra (and is the one they use in the Infinity software). Not exactly field friendly but if you are capable in excel you can pull info from a ballistics program and plug it into this formula to make your own table/card.
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/3.438) = Corrected MIL Sight Adjustment
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/1) = Corrected MOA Sight Adjustment
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/.955) = Corrected IPHY Sight Adjustment
The actual formula used for Mils set up for 1/10th mil "clicks"
=ROUND((((((E3-1)*'Data Sheet'!E36)+'Data Sheet'!F36)/((A15/100)*1.047)*'Data Sheet'!O3)/3.438)*10,0)/10*-1
Of course that formula is worthless unless you know what the "Data Sheet" looks like
Cheers,
Doc
What units are used in this formula for Bullet path and range?
((((Bullet Drop (+) * (1.0 - cosine of angle)) + Bullet Path) / ((Range/100)*1.047)/3.438) = Corrected MIL Sight Adjustment
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